Re: Calling an external command from a Haskell program

Adrian Hey <ahey@iee.org> writes:

On Wednesday 15 Oct 2003 8:44 am, Salvador Lucas wrote:

...

Dear all,

I think this question is not new, but I am not able to find the answer. How to proceed to execute an external Linux command (e.g., 'ls') from a Haskell program?

Thanks in advance,

You can use.. system :: String -> IO ExitCode in library module System.Cmd

If you want access to its I/O streams as well, you can use Posix.popen, which is not standard Haskell 98, I think, but it's in GHC. -- Looks up a word by passing it to `cmafihe'. cmafihe :: String -> IO String cmafihe word = popen cmafihePath [] (Just word) >>= return . fst3 where cmafihePath = "/usr/local/bin/cmafihe" fst3 (a, b, c) = a